package com.mmdccj.reggie.controller;

import com.mmdccj.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {
    // 获取application.yml定义的路径
    @Value("${reggie.path}")
    private String basePath;

    /***
     * 接收前端上传的数据
     * @param file
     * @return 上传结果
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file) {
        if (file == null) {
            return R.error("上传文件为空");
        }
        //原始文件名
        String originalFilename = file.getOriginalFilename();//abc.jpg
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用UUID重新生成文件名，防止文件名称重复造成文件覆盖
        String fileName = UUID.randomUUID().toString() + suffix;

        //创建一个目录对象
        File dir = new File(basePath);
        //判断当前目录是否存在
        if (!dir.exists()) {
            //目录不存在，需要创建
            dir.mkdirs();
        }
        try {
            //将临时文件转存到指定位置
            file.transferTo(new File(basePath + fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(fileName);
    }

    /***
     * 前端上传图片后再次返回上传的图片到浏览器
     * @param name 文件名
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response) {
        log.info("name是"+name);
        try {
            FileInputStream fileIn =
                    new FileInputStream(new File(basePath + name));
            ServletOutputStream fileOut =
                    response.getOutputStream();
            response.setContentType("image/jpeg");
            int len = 0;
            byte[] b = new byte[1024];
            while ((len = fileIn.read(b)) != -1) {
                fileOut.write(b, 0, len);
                fileOut.flush();
            }
            // 传输完成后关闭管道
            fileOut.close();
            fileIn.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
